Current collector system



Nov. 11, 1941. c. c. WHITTAKER buRRENT COLLECTOR SYSTEM Filed Aug. 18, 1939 V 2' Sheets-Sheet 1 WITNESSES:

INVENTOR Char/e5 6'. Wfz zZzake/t B V Z S WTOR Y 2 Sheets-Sheet 2 C. C. WHITTAKER CURRENT COLLECTOR SYSTEM Flled Aug, 18, 1939 /9 4 l l l l 1 Nov. 11, 1941.

Patented Nov. 11, 1941 UNITED [STAT CURRENT COLLECTOR SYSTEM Charles C. WhittakenPittsburgh, Pa., assignor is 1 Westinghouse Electric& Manufacturing Com- -pany, East Pittsburgh, Pa., a corporation of Pennsylvania Application Au esus, 1939, Serial No. 29;),775

3 Claims. (01. 191-4) 1 My invention relates generally to current collectors, and it has reference, in particular, to a control system. for current collectors.

It is an object of my invention, generally stated, to provide a simple and effective manner for controlling the connections of current collectors on an electrically operated vehicle.

More specifically, it is. an object of my invention to provide for connecting a current collector on a vehicle to a. power bus when the collector is operated to an energized position, and connecting it to ground when it is operated to a deenergized position. 1 r r .Another object of my invention is to provide for grounding a current collector ona vehicle when it is in the deenergized position, and disconnecting the current collector from ground upon the operation=of the current collector. to an energized position, and prevent operation .of. the current collector to the energized position before it is disconnected from ground. A further object of my invention is to provide control means responsive to the movement of a current collector on a vehicle to apredetermined position for selectively controlling the connection of the current collector; to a power bus, i

Yet another object of my invention is to provide in a safe and. efficient manner for automatically grounding a current collector on an electrically operated vehicle. a d I .qAnother important object of my invention is to provide a combined-ground and power switch for a current collector on an electrically operated vehicle, for controlling the connection-ofthe current collector in accordance with its posi- 1 Otherobjects will, in part, be obvious and will, in part, appear hereinafter. 4 i In practicing my invention, suitable switching means may be provided for, selectively connecting a current collector on an electrically operated vehicle, either to apower bus for supplying power to the vehicle motors, or to a ground connection so that inspection or repair of the current collectormaybe made in safety. Since in'some instances" the difference between the minimum operating height of a current collector andthe locked-downer deenergized position is relatively small, Lpreferto control theoperation of the switching means by a suitable control means, which maybe responsive to movement of the current collector as it is operated to the deenergized position. Inorder to insure that the current collector willbe grounded when in the deenergized position, and will not be operated to the energized position while grounded, the switching means may has been actuated to disconnect the current 001-.

taken in connection be normally disposed to connect the current collector to ground, and adapted upon energization to connect it to the power bus, so that any failure of the control system will not prevent the grounding .of' the. current collector in the deenergized positionpand, in addition, the switching means may be provided with a safety latch device for preventing actuation of the current collector to. the. energized position until the switching means lector from ground.- a

For a more complete understanding of the natureand scope of my invention, reference may be had to the following detailed description,

with the accompanying drawings, inwhich: i Figure 1 is a plan view. of a pantograph type current collector embodying my invention;

Fig. 2 is a diagrammatic view of a current collector system employing current collectors of the pantograph type and embodying the invention; Fig. 3 is an enlarged .view, in section, of one form of, auxiliary or control switch utilized inthe system. shown in Fig. 2; i Fig.4 represents diagrammatically a current collector system employing current collectorsof another type, and embodying the invention; and Fig. 5is an enlarged view of another form of auxiliaryor control switch. r Referring particularly to Fig. l, the reference numeral 10 may denote generally a current cola lector of any suitable type, comprising, forexample, an elongated slider shoe 12 which is mounted on a pantograph supporting structure l4 for engaging an overhead trolley conductor [6. The pantograph structure I4 may be mounted on a suitable frame l8, and supported on the roof oi an electrically operated vehicle (not shown) by means of insulators 20,

M In order ,to'urge the slider with the trolley conductor l6, suitable means, such-as the springs 22, may be provided foreffecting rotation of shafts 24 to whichthe pantograph structure I4 is attached, through the medium of earns 26 which are secured thereto. Actuating means, such as fluid-pressure operated devices 28, may be provided for lowering the pantograph structure M to the deenergized position against the force of the springs 22. For example, the fluid pressure devices 28 may be connected to bell crank levers 30 which are attached to the rotatable shafts 24 of the pantograph supporting structure l6, for rotating them against 5 the force-applied by the springs 22.

shoe l2 into contact Retaining means of any well-known type, such as a pivoted latch member 32, which is best shown in Fig. 2 may be provided, having means, such as a spring 33, for normally retaining the latch in position for engaging the pantograph frame I4, so as to automatically secure the current collector in the deenergized position after it has been lowered by operation of the fluid pressure device 28'. Release of the latch member 32 may be effected by means, such as the fluid pressure device 34, which may be operatively connected to the latch member 32 for actuating it to disengage the supporting structure, and release the current col.- lector from the deenergized position.

Referring particularly to Fig. 2, the reference numeral 35 denotes generally a current collector system having a pair of current collectors III of the type illustrated in Fig. 1, which may be mounted on the roof of a vehicle. Inasmuch as the circuits, apparatusand structure associated with each of the current collectors are the same, the like elements of each are similarly numbered, so that the description is equally applicable to both.

Accordingly, the reference numeral 36 denotes generally a switch which may be operated to connect the current collector I either to a power bus 38 through which power may be supplied to the motors (not shown) of the vehicle, or to a suitable ground connection 42 which may be connected to the metal frame or roof 43 of the vehicle. The switch 36 may be of any suitable type, comprising, for example, a pivoted contact arm 44, which may be operatively connected to an actuating member 48 by means of a pin 50 slidably positioned in a slot 52 therein, so as to provide a certain amount of lost motion between the actuating member 48 and the contact arm 44, in order that the actuating member 48 may deliver a hammer-like blow to the contact arm 44 for operating it, to overcome any tendency of the contact arm to freeze to either the power bus 38 or the ground connection 42. I

The actuating member 48 may be actuated in any suitable manner, being, for example, operatively connected to the piston 53 of a fluid pressure device 54, and insulated therefrom by means of an insulator 56. Suitable means, such as a spring 58, may be provided for urging the piston 52 downwardly to normally connect the contact arm 44 to the ground connection 42 and ground the current collector I0.

In order to control the operation of the fluid pressure device 28 for lowering the pantograph structure, the fluid pressure device 34 for releasing the latch 32, and the fluid pressure device 54 of the switch 36, suitable control means, such as the electro-pneumatic valves 60, 62 and 64, may be provided for controlling the application of fluid pressure to the fluid pressure devices 28, 34 and 54, respectively, from a suitable source of fluid pressure, such as the reservoir 66, and exhausting the fluid pressure therefrom. The operating windings 68, I0 and I2 of the control valves 60, 62 and 64, respectively, may be energized from a suitable source of control potential, such as a battery I4. For example, up pushbuttons 16 may be provided at each end of the vehicle for energizing the operating windings of the control valves 62 and 64 at the opposite end of the vehicle, while down pushbuttons 18 may be provided at each end of the vehicle for effecting energization of the operating windings of the control valves 60 at both ends of the vehicle.

In order to provide for operating the fluid pressure devices 34 to release the pantograph structure I4 from the deenergized position when there is no fluid pressure available in the reservoir 66, a hand pump may be connected in the fluid pressure system. Suitable check valves 82 may be provided in the fluid pressure system for permitting the flow of the pressure fluid in one direction only, as desired.

In order to control the operation of the switch 36, in accordance with the movement of the current collector slider shoe I2 to a predetermined position, means, such as the auxiliary or control switch 84, may be provided, which may be actuated in response to the movement of the slider shoe I2 as it approaches the deenergized or locked-down position. For example, a suitable stop member 66 may be provided on support structure I4, or on the underside of the slider shoe I2, to actuate the auxiliary switch 84 as the slider shoe approaches the denergized or lockeddown position. By controlling the energization of the operating windings of the control valves 64 through the contact members of the auxiliary switch 84, the operation of the switch 36 may be so controlled, in accordance with the position of the slider shoe I2, that the slider shoe I2 will be grounded when it is actuated to the deenergized position, and will be disconnected from ground when it is actuated to the energized position.

In order to prevent actuation of the current collector I0 to the energized position before it is disconnected from ground, means may be provided for interlocking the operation of the switch 36 and the pantograph structure I4. For example, a slidable safety latch may be provided, and operatively connected to the contact arm 44 of the ground switch 36, through means, such as the bell crank lever 92, so that when the pantograph structure I4 is lowered and the switch 36 operated to ground the current collector I0, the latch 90 will engage the pantograph structure I4. In this manner, the pantograph structure I4 cannot be raised until the switch 36 has been operated to disconnect the contact arm 44 from the ground connection 42, and thus release the safety latch 90 from engagement with the pantograph support structure I4.

Referring particularly to Fig. 3 of the drawings, the reference numeral 84 denotes generally one form which the auxiliary or control switch for controlling the operation of the switch 36, in accordance with the position of the current collectors, may take. For example, a pillar-type insulator I00 may be provided having a central opening I02 therethrough and a suitable flanged base I04 secured thereto in any desirable manner. An adapter ring I06 may be secured thereto, having the lower surface adapted to fit the contour of the roof 43 of the vehicle on which the switch is to be mounted, and the upper face adapted to fit with the flanged base I04, for

facilitating positioning the switch on the roof of the vehicle.

Pairs of stationary contact members 84a and 84b may be positioned within the insulator in any suitable manner, being, for example, mounted on an insulating plate II2 which may be secured to the flanged base I 04 of the insulator in any suitable manner, such as by means of bolts II4. A bridging member I I6 may be movably positioned for bridging either the stationary contact members 84a or 84b, being, for example, mounted on, and actuated by an axially positioned insulating rod I20, within the insulator, which projects above the top of the insulator for engagement with the stop member 86 of thecurrent collector.

A sealed j ointmay be provided between the insulating rod I20 andthe insulator I atthe upper endffor permitting actuation of the rod I20 in response to movement of the current collector, relative to the insulator, in any suitable manner,

ing winding 12, through conductor I60, winding 12, contact members 84a, and conductor I62 to conductor I46, so that the valve 64 is maintained such as, for example, by utilizing a flexible member, such as the metallic bellowsmember I24. The lower end of the bellows member may be secured to the insulator by means of a, nipple I26, which may be threadedly engagedwith a flanged end member I28 on the insulator, and the upper end thereof may be attached to the insulator rod I 20', by suitable means, such as thescrew I30. Biasing means, such as the spring I32 may be provided for urgingthe insulating rod I20 upwardly sothat the bridging member II6 normally engages the stationary contact'members 84a. to provide a circuit therebetween. A cover member I34 may be provided for enclosing the contact members 84a and 84b, being secured to the switch in any suitable manner, such as by means of the tap bolts I36,so that it may: be readily removedfor purposes of inspection or repair.

i It is usual with a vehicle having current collectors ateach end, to use the current collector at the trailing end of the vehicle with the operator positioned atthe leading end. In order to releasethe trailing current collectorl0 at the right-hand side of Fig. 2 from thelocked-down, or 'deenergized position, the up pushbutton 16, which is positioned toward the left-hand side of the figure, maybe closed momentarily for effecting energization of the operating winding of the electro-pneumatic valve 62 which controls the application of fluid pressure to the fluid pressure device 34 of the latch 32. The energizing circuit may be traced from the battery 14through conductor I40, conductor I42, push-button 16,

conductor I44, operating winding10, and conductor I46 back to the battery 14., Operation oi. the valve 62 connects the fluid pressure device 34 to the source of fluid pressure 66, through the conduit I48, electro-pneumatic valve62, check valve 82,.and conduit I52. The latch 321s then actuated to release the pantograph structure I4. Upon the release of the pushbutton 16, the valve 62 returns to the deenergized position, and the fluid pressure device 34 is exhausted so that the spring 33 returns the latch member 32 to the engaging position where it is ready to engage the pantograph structure I4 when it is lowered.

r At thesame time that the operating winding 10 of the electro-pneumatic valve 62 is energized, the operating winding 12 of the electro-pneumatic valve 64 is also energized. The energizing circuit, therefore, may be traced from the battery 14, through conductor I40, conductor I42, pushbutton 16, conductor I44, conductor I56, contact members 84b, operating winding 12, conductor I60, and conductor I46 back to the batgraph structure I4, which may then be raised to the energized position under the action of the springs 22. 1

Upon the release of the current collector from the deenergized or locked-down position, the auxiliary switch 84 functions, opening contact members 84b and closing contact members 840., to complete a shunt holding circuit for the operatin the energizedposition, thus retaining fluid pressure on the fluid pressure device 54, so that the switch 36 is held closed and the current collector is connected to the power bus 38. i In order to lower the current collector I0 from the energized position, the down pushbutton 18 may be closed for effecting simultaneous energizationof the operating windings 68 of the electro-pneumatic valves from either end of the vehicle, to admit fluid pressure to the fluid pressure devices 28, which are adapted to actuate the pantograph structure I4 to the deenergized or locked-down position.

Upon the lowering of the pantograph structure 14, the auxiliary switch 84 will be actuated by the stop member 86 which engages it. The energizing circuit for the operating winding 12 of the valve 64 is interrupted by the openingof the contact members 840. of the auxiliary switch 84, so that the connection of the fluid pressure device 54 to the source or fluid pressure isterminated and it is exhausted. The spring 58 then actuates the operating member 48, whichpopcrates the switch arm 44 to disconnect the current collector I0 from the power bus .38 and ground it through the ground connection 42.

When the pantograph structure I4 reaches the deenergized positiomthe latch 32 then engages the pantograph structure I4 .to retain it in this position until the latch is subsequently operated by the application of the fluid pressure to the fluid pressure device 32, as hereinbefore -de.-

scribed, to release the. pantographstructure. 1

Referring particularly to Fig. 4, the reference numerals I10 denote current collector supports of the trolley-pole type having ropes I12,attached thereto for raising and lowering them. The trolley poles I10 are adapted to be mounted on the roof I 14 of an electrically operated .vehicle and insulated therefrom by means of insulation I16, for supporting current collectors I18 of any suitable type. Means, such as the hook devices I80, may be provided for securing the trolley poles in the down or deenergized position. These hook devices may likewise be mounted on I the roof I14 of the vehicle, and insulated therefrom by means of suitable insulation I11;

In order to control the electrical connections of the current collectors I18, which are mounted on the trolley poles I10, suitable means, such as the switches I82, may be provided, having operating windings I84, contact members I82a through which the current collectors may be connected to a power bus I86 for supplying power to the motors of the vehicle (not shown), and contact members I82b through which the current collectors I18 may be connected to ground. Auxiliary or control means I88 may be provided in association with the hook members I for controlling the energization of the operating windings I84 in accordance, with the movement of the current collectors I18 to predetermined positions. Referring particularly, to Fig. 5, it may be seen that the control means I88 may comprise a suitable switch, such as the mercury switch I90,

which may be mounted on a pivoted switch arm I92 normally biased to the position in which it is shown by means, such as the spring I93, and

which is adapted to be engaged by a trolley pole as it is moved to the deenergized position in the hook member I80. Engagement of the trolley pole with the switch arm I82 actuates the switch arm I92 to the position shown in the dotted outline, so that the mercury switch I90 is tilted, and the connection between the contacts thereof is broken. The operating windings I84 of the switches I82 may be connected in series circuit relation with their respective auxiliary or control switches I88 to a suitable source of power, such as the battery I 94. Thus, when the trolley poles are in the deenergized position, the circuits through the auxiliary or control means I88 are broken, and the operating windings of the switches I82 are deenergized, so that the switches l8'2'are actuated by gravity or other suitable means to close the contact members 1821) to connect the current collectors I18 to ground.

Upon the operation of either or both of the current collectors to the energized position, the control circuit through the mercury switch I90 is restored and the energizing circuit for the operating coil of the switch device will be completed, causing operation of a switch device to connect the current collector to the power bus I86.

From the above-detailed description, taken in connection with the accompanying drawings, it will be realized that I have in my invention provided in a simple and effective manner for automatically controlling the connection of a current collector on a vehicle either to ground or to a power bus, in accordance with the operating position of the current collector. By controlling the connection of the current collector in this manner, positive disconnection of the current collector from the power bus and the connection thereof to ground are insured when the current collector is moved to the locked-down or deenergized position, so as to properly protect a workman coming in contact therewith, and disconnection of the current collector from ground and its connection to the'power bus are effected as soon as the current collector is released from the deenergized position.

Since certain changes may be made in the above description, and different embodiments of the invention may be made without departing from the spirit thereof, it is intended that all the matter contained in the above description, or shown in the accompanying drawings, shall be considered as illustrative and not in a limiting sense.

I claim as my invention:

1. A current collecting system comprising a pair of current collectors, support means for the current collectors adapted to urge the current 001- lectors into engagement with a conductor, fluid pressure means for actuating the current collectors to the deenergized position, latch means for retaining the current collectors in the deenergized position, a power bus, switch means associated with each" current collector for'connecting the current collector to ground in the deenergized position, control means for effecting operation of the latch means to release the current collector from the deenergized position, relay means operable upon actuation of the control means to effect operation of the switch means to connect the current collector to the power bus, and control switch means responsive to the ree lease of the current collectors from the deenergized-position to provide for maintaining the connection of the switch means to the power bus.

2. A current collecting system comprising, a current collector, a pantograph support structure for urging the current collector against a trolley conductor, fluid pressure means for actuating the pantograph structure to a deenergized position, latch means for engaging the pantograph structure to retain the current collector in the deenergized position actuable by fluid pressure to release the pantograph structure to efiect actuation of the current collector to the energized position, a power bus, a ground connection, switch means selectively" operable to connect the current collector to the power bus or to the ground connection, an auxiliary switch responsive to operation of the pantograph structure to control the operation of the switch means, and additional latch means adapted to prevent release of the pantograph structure from the deenergized position before operation of the switch means to connect the current collector to the power bus.

3. A current collecting system comprising, a current-collector, a supporting structure for urging the current collector against a conductor, fluid pressure means for efiecting operation of the supporting structure to actuate the current collector to a deenergized position, latch means to retain the current collector in the deenergized position, a power bus, a ground connection, fluid pressure operated switch means normally connecting the current collector to the ground connection operable to connect the current collector to the power bus, an electro-responsive valve energizable to apply fluid pressure to the switch operating means, means to actuate the current collector to a deenergized position, and an auxiliary switch responsive to actuation of the current collector to the deenergized position to deenergize the electro-responsive valve means to effect operation of the switch means to disconnect the current collector from the power bus and connect it to the ground connection, and set up a control circuit for releasing the latch means.

CHARLES C. WHITTAKER. 

